Starting and speed-limiting device for electric motors



I. E. FELLER. STARTING AND SPEED LIMITING DEVICE FOR ELECTRIC MOTORS.-

2 SHEETS-SHEET l.

Wa Mu Elwin/Mm ga -R flttozuuf Patented Feb. 8,1921.

APPLICATION FILED APR-13,1?-

r J. E. FELLER. STABTHIG AND SPEED LIMITING DEVICE FOR ELECTRIC MOTORS.

APPLICATIDN F ILED APR. 13; 1917- Patented Feb.8, 1921.

2 SHEETS-SHEET -2.

gum/Moi PATENT OFFICE.

JOSEPH E. FELLER, OF BROOKLYN, NEW YORK.

STARTING AND SPEED-LIMITING DEVICE ron ELECTRIC MOTORS.

necmoe.

Specification of Letters Patent.

Patented Feb. 8, 1921.

Application filed April 13 1917. Serial No. 161,765.

To all whom it may concern:

Be it knownthat 1,. .losnrn Famine, a citizen of the United States, residing at- Brooklyn, iii-the county of Kings state of New York, have invented certain new and useful improvements in Starting and Speed- .l imiting Devices for Electric Motors, of which the following a full and clear specification. g g

-This invention relates to means for automatically controlling the operation of electric motors and has" for its primary object to provide an improved operating system, according to which the acceleration ofthe motor during the starting period is made to depend upon the current input to the motor and not upon the line voltage. The present invention contemplates an operating system for electric motors in which-an abnormally weak field, anopen circuit in the field or its connections. an open circuit in theiield rheostat, or a faulty contact in the field circuit,

causes the motorto stop, it running, and it the motor is not running, prevents it being started. One of the objects of the present invention is to provide improved means for accomplishing these results without the blowing ot fuses, opening of circuit breakers. and without dannige to the motor or to any of the apparatus 'Anotherobject is to provide im jn'oved means for automatt. cally iregulatingthe sensibility of the circuit breaker to correspond to condltions at start in g and while running, thus affording proper protection to the apparatus under all condi tions. Other and further objects will appear in the s iecitication and be pointed out in the appended claims, reference being had to the accompanying drawings which ex emplity my invention in a preferred embodi nicnt. i i 1 lnthe drawings 3 Figure 1 is a wiring"diagramaccording to this embodiment of my invention;

Fig. 2 shows a portion of this diagram on an enlarged scale with the parts in different positions.

.lleterring more particularly to the draw- .ings the parts will be referredto in the order in which they occurin the various circuits. Thus in the present embodiment of my invention, av positive main 1 is connected to a wire 2 from which extends a wire 3 leading to one brush of an armature 4 of a :fractjional horse power pilotmotor the other ln'ush ot' said armature being connected by a wire 5 to a fixed contact 6. A movable contact 7 1s yieldably mounted on one arm 8 of a lever which is pivotally mountedat 9 and connected by a wire 10 to a fixed contact 11 with which cooperates a contact 12, yielda-bly mounted on one arm 13 of a lever pivoted at 14; and acted upon by a tension spring 15. A wire 16 leads from the pivot 1401 lever 13 to a fixed contact 17. A wire 18 leads fromthe contact 17 to a fixed contact 19. A contact 20 is adapted to be yieldably pressed against the fixed contact 19 by a lever arm 21 which carries a pin 22 with which engages the hook arm 23 of a lever ful crumed at 24, a wire 25 leading from the fulcrum 24 to the negative main 26. A branch wire 27 leads from the positive main 1 to a coil or magnet 28, the other terminal of said coil or magnet being connected by a wire 29 to a fixed contact 30 which is spaced from the contact 17 and adapted to be connected thereto by a pivotally mounted switch lever 31.. The line wire 2 is electricallv connected. to the journal 32 of a rheostat arm 33 which is adapted to more .snccessivelv over the contacts 3 1 for cutting out successive portions ot the resistance. The last contact 34 is connected by a wire 35 to one terminal of a field winding 36 of the pilot motor. the other terminal of the winding 36 being con nected by a wire 3'? to a wire 38 whicli leads to one end of an overload winding 39. The other end of the winding 39 is connected b3 a wire 10 to onobrush of the armature 41 the other brush of said armature being con nected by a wire 42. to an oscillatory contact which is adapted to be magnetically operated by the coil or magnet 28 to be moved into engagement with alixed contact 44 connected with a blow-out coil 45, the other end of the blow-out coil. 45 being connected by a wire 4.6 to the negative main 26. Connected to the wire2, is a solenoid or winding 47, which when energized, magnetically clutches the rheostat arm 33 to the gear 51 which is driven by the pilot motor through the worm 50. Awire 48 leads from coil 47 to the field winding 4-9 of the pilot motor, said field winding 49' being also connected to the negative line leading from the pilot motor armature and including contacts 11 and 12 and circuit breaker contacts'19 and 20. \Vhenever the rheostat arm 33 is magnetically clutched to the worm gear 51, said arm is caused to travel over the contacts 34 in succession until it reaches a. contact 52 which is connected by a wire 53 to one terminal of a magnet 54, the other erminal of said magnet being con nected by a wire 5.3 to the wire 1%) hereinbctore referred to. Whenever the magnet 54. is energized, it attracts an armature lever 56 which swings about a pivot 57 and is connected to the wire 3*. The armature 31'; carries a contact which is bri'iught against the lixed contact as) to which is connected one end of a blow-out coil no, the other end of said blow-out coil being connected to a line wire 61, le.a .ling t cm the positive main 1. A wire (32 leads from the positive wire 2 to a field rheostat (i i which is connect ac by another wire tie. to a magnet 35. .1 wir (is connects magnet 65 'o lield winding (3 the main motor. '1

said i connected bv the wire (3R to the negative hue from motor armature 4- 3 connected to the lever l and when attracted b) magnet closes contacts it and 12. The armature lever 56 is provided with a late: ally projecting arm 69 adapted to depress a reciproca le bolt TO which engages one arm it of a lever otcd i at T2, the other arm T?) of said lever b dapted its extremity to engage one arm Tl of the lever pivoted at at the energization of the magnet 5- being' therefore adapted to open the contacts (3 and T and thereby interrupting the operation o he pilot in itor. A pendulum-like lever T; i' pivoted at T6 to the lever arm i l 2nd has deflected end 7? which carries an adjustable abutment tor determining the lower limit of an armature lever T9 which is pivoted at H and :dapted to be raised h v the overload solenoic 39 when the degree of energization reaches a cer; in prialetermiued undesirable amount. )1 scale plate 91 I11;1 be provided tor indicating the amperage within the solenoid coil 35) which will result in a lifting movement to the armature Ti \Vhenever the armature T9 is thus lifted i raps the arm 82 of the lever pivoted at and thereby depresses the other arm disengage it from the pin 'lhercupon the arm 21 which carries the cieldabl mounted FOUtHCt 20 is swum: about its center 5 -1. a spring until it strikes 1. stop I. handle 86 adapts the to he reti rued to normal position tor the circuit breaker.

The ope ation of n improved system may be briefly described as follows: Suppose both lllOt'OlS to be at rest, the switch being in the position shown in Fig. 1 the contacts ll and 12 shown in Fig. 1 being opened, and the parts shown in Fig. 2 being in full line positions. lihen the switch 31 is moved to bridge the gap between contacts 30 and 17, the following circuit is establislnal: pi sitivc main 1. wire 2?, magnet 28, wire 29, contact 30, switch 31. contact 17. wire 18, contacts 19 and 2t arm pin 22. lever 23. pivot 21. wire 2:", and negative main 26. Magnet 28 lever 2 being energized, attracts armature contact i3. thus closing the lidtowiag circuit: positive main 1, wire 62, rheostat (53, wire ti l, magnet 65, wire 66, field winding 6? (of: the main motor), wire 42, armature conact 43, contact 44:. blow-out coil l5. wire 4:, and negative main 2o. This circuit energizes magnet 65, which operating on armature 69. closes contacts 11 and 12. At the same time field winding 67 is energized. By closing the contacts 11 and 12 the following circuit is cstaliilishcdz positive main wir 2, wire 3. pilot motor armature 4, wire contacts 6 and '7, lever 8, pivot 9, wire 10. contacts 1.1. and 12, lever 13, pivot lat, wire 16, wire 18, contacts 19 and 2t), arm 21, pin 22 lever 23. wire 25. and negative main 2(5. Simultaneously a branch circuit is established through wire 2, winding 4:7, wire d8, field winding 49 of the pilot motor and the negative line leading from pilot motor armature 4. The energization of winding l7 serves to ellcct a magnetic clutch between the hub portion of rheostatarm 33 and the gear 51 so that the rheostat arm SlOWl" moved in a clockwise dircction by the pilot motor. .is the rheostat arm moves in a clockwise direction. the following circuit s made: positive main 1, wiri arm 53, contacts S t and resistance connected thereto. wire 35, field .vimling 36 of the pilot motor, wire 3?, wire 38. circuit breaker coil 39, wire 10, main motor a ma tare ell, wire 42, contacts i and ll, blowout coil 45, wire 46, and negative :nain on. As the main motor accelerates the angula speed of rheostat arm 33 will depend upon the amount of current in the pilot motor coil 36 which is connected up in series vith the circuit breaker coil 39 and armature a l, l1: will be seen therefore that the speed of the pilot motor will be regulated by the current input to the armature of the main mot-or. lVhen the .rheostat arm has reached conact a shunt circuit is established through wire 2, rheostatarm 33, contact wire 523. magnet 54-, wire 55, and negative line from wire 10. The cnergization of magnet 54 attracts :rmatnre 56 and closes contacts and 59 to establish a main motor circuit independently of the pilot motor. as 'loll:;nv.-s: positive main 1. wire 61. blow-out coil (30. contacts 59 and 5S, arm 56, wire 38, winding 39, wire-ll), armature :41, and negative line from the main motor. At the same time, lever 73 is shifted to full line position shown in Fig. 1 which opens Contacts (3 and T and interrupts the movement oi the pilot motor and permits the rhcostat arm 33 to return to its original position shown in Fi 1. The en .rgization of magnet fi l is sieataincd b v closing contacts 97 and 88, the latter being connected by a wire 89 to the wire 53 which leads to magnet 5d. When the lever 73 is made to assume the full line position shown in Fig. 1 the circuit breaker armature T9 is ion ll l

raised to a position in which. it will react more readily to an overload, the scale plate 81 being provided to indicate the current necessary to operate the armature 79 in various; positions. Should the system be exposed to excessive load at any time, the upward movement of armature 79 moves the lever 23-82 to release the arm 21 which breaks open thecontacts l9 and 21,. deiinergizes magnet 28, and opens the main motor circuit at contacts a3 and .44. If the field strength of the motor becomes weakened below a predetermined minimum, or if for anyreason the field circuit becomes impaired or damaged, the holding in coil'65 releases armature 7 9 and breaks the circuit at contacts 11. and 12. This action also shuts down the motori'f running, and it the motor is not running, said motor will not start under these conditions. If for any reason the motor stops by reason of a failure in the current supply, it will be ready to start up again undernormal, fully protected conditions as soon as theqcurrent supply is "reestablished. The leading advantages accruin to this system are that the acceleration in the motors speed is. dependent on the current input to the motor and not onthe line voltage; such acceleration is fast or slowaccording to whether the current input to the motor is light or heavy, and is therefore absolutely automatic and self regulating. An abnormally weak field, an open circuit in the field, in its connections, in thefield rheostat, or a faulty contact in the field circuit, causes the motor to stop, if running, and if not running,

it will not start v under these conditions. These results are accomplished without the blowingfiof fuses, or damage to the motor or to any of the apparatus. The circuit breaker is arranged to protect the motor while it is being started as well as while it is running. The undesirable but'usual practice of operators in setting Well known types of circuitflbreakers so as not to trip while the motor is. being started, is obviated by this system. Among other fields of service, this invention is peculiarlyserviceable for use in connection with forced draft blowing motors and ventilating sets on shipboard for example Where much confusion, lossof time, blowing of fuses, and damage to apparatus in general is oftenoccasioned by the reestablishment of current after a shut down. According to my inventionsuch a motor will start from zero. conditions as soon as cur rent is reestablished. In, radio Work, it is especially desirable to start and stop the radio motor generator with, certainty, with speed, and without damaging the motor or the starter. Myinvention completely protects the radio apparatus from delay or damage due to conditionsin the motor field circuit and can be readily adapted for use on starting panels atpresent in use.

I claim:

1. In a system of the character described, a motor to be started and czmtrolled, a starting circuit therefor, a running circuit, a relay for changing from the starting to the running circuit, an energizing circuit for said relay including separable contacts, a field energizing circuit, and a holding-in coil for operating said contacts included in said field energizing circuit.

In apparatus of the character described, a main motor, a pilot motor, a starting circuit for said main motor including a pilot motor field winding in series with the main motor armature, a running circuit for said main motor including a relay and a circuit breaker, and means under the control of said relay for controlling the operation of said circuit breaker.

3. In a system of the character described, a. main motor, a starting circuit therefor, a pilot motor for controlling said starting circuit, an operating circuit for said pilot 'motor, a running circuit for said main motor, means under the control of said starting circuit for establishing said main motor running circuit, and means under the control of said main motor running circuit for breaking said starting circuit.

-il. In apparatusof the character described, a main motor, a rheostat therefor, a pilot motor for operating said rheostat, said pilot motor, having a. field Winding connected up in series with said main motor during the starting period, a relay provided with a switch controlling the main motor starting circuit, a circuit breaker controlling the energization of said relay, a running circuit for the main motor, a second relay for controlling said running circuit, and means operated by the second relay for controlling the operation of said circuit breaker.

In a system of the character described. a motor, a running circuit therefor, arelay for controlling said running circuit. a starting circuit for said motor including a branch for energizing said relay, an overload circuit breaker for said running circuit, and means operated by said relay for changing the degree of sensitiveness of said overload circuit breaker.

6. In apparatus of the character described, a main motor, a starting circ'uittherefor, a pilot motor for controlling said starting circuit, said starting circuit including a pilot motor field winding and main motor armature,-a running circuit for said main motor, a relay for controlling saidrunning circuit, and an overload circuit breaker under the control of said relay.

7. In apparatus of the character described, a main motor having an armature and field winding, a rheostat for said motor, a pilot motor foroperating said rheostat, a circuit for energizing the main motor armature, in-

eluding a pilot motor iield in series with said rheostat, a relay. a circuit independent ot the rheostat resistance t'or energizing said relay, a circuit under the control of said rclay and independent of said rheostat and pilot motor field tor energizing said armature, an energizing circuit tor the pilot motor armature including separable contacts. means operated by said relay for opening said contacts, and a circuit breaker which controls the energizing circuit tor said relay,

said circuit-breaker having a magnetic coil in circuit with the main motor armature.

S. In apparatusot the character described. a main motor. a starting circuit therefor, a pilot motor for controlling said starting circuit. said. starting circuit including a pilot motor field winding and main motor armature. a running circuit il'or said main motor, a relay for controlling said running circuit, and an overload circuit breaker under the control of said relay, said starting circuit including a resistance branch which excludes said relay, and another branch which includes said relay but excludes said resistance branch.

9. In a system 01 the character described, a main motor provided with an armature and a field winding, a holding-in coil in circuit with said field winding, 21 starting rheostat tor the main motor, a pilot motor for operating said rheostat. an energizing circuit tor said pilot motor including separable contacts subject to the control oi said holding-in coil, said pilot motor being provided with a field winding in circuit with the armature ot' said main motor, a running circuit for said main motor, and a relay connected up in circuit with said separable contacts for controlling said running circuit.

10. in a system oi? the character described, a main motor provided with an armatureand a tield winding, a holding-in coil in circuit with said fi ld winding, a starting rheostat for the main motor, a pilot motor for operating said rheostat, an energizing circuit tor said pilot mot-or including separable contacts subject to the control of said holding-in coil, said pilot motor being provided with a field winding in circuit with the armature of said main motor, a running circuit for said main motor, a relay connected up in circuit with said separable contacts for controlling said running circuit, other separable contacts in the pilot motor energizing circuit, and means operated by said relay for separating said other contacts, said relay being provided with means for closing a substitute circuit for maintaining the energization of said relay.

11. In a system of the character described, a motor, a starting circuitthereit'or, relay, a running circuit for said motor under the control of said relay, said running circuit including separable contacts, a holding-in coil for said contacts, a tield winding tor said motor in series with said holding-in coil, and a pilot motor for controlling said starting circuit, said pilot motor being provided with a field winding in series with the armature ot the first mentioned motor, and another tield winding under the control oi said relay.

12.111 apparatus of the character described, a main motor, a starting circuit therefor, a pilot motor for controlling said starting circuit, said starting circuit including a pilot motor field winding and main motor armature, a running circuit for said main motor, a relay tor controlling said running circuit, and an overload circuit breaker under the control of said relay, said starting circuit including a rheostat arm, a magnetic clutch for connecting said rhoostat arm to said pilot motor, and means under the control of said relay for breaking said starting circuit.

13. In a system of the character described, a motor, a starting circuit tor said motor, a circuit ireaker having an overload coil included in said starting circuit, a relay, means for breaking said starting circuit and energizing said relay, a running circuit for said motor established by said relay to include said overload coil, said starting circuit including separable contacts other than those in said circuit breaker, a holding-in coil for holding said other contacts closed, and a field winding circuit 'for the motor including said holding-in coil.

ll. In a system of the character described, a main motor, a running circuit therefor, a relay for controlling said running circuit, a pilot motor armature, astarting rheostat. for said main motor including an arm moved by said pilot motor armature, a field winding for said pilot motor armature connected up in series with said rhcostat and the armature ot said main motor, a branch circuit coir nected with said rheostat tor cnergiying said relay, a second field winding for said pilot motor armature, an energizing circuit for said pilot motor armature and second field winding, including separable contacts, and means operated by said relay for controlling said separable contacts.

15. In a system of the character described, a main motor, a running circuit theretor including a relay switch and a circuit breaker other than said relay switch, a starting circuit for said main motor comprising a rheostat branch and a second branch excluding said rheostat, a relay magnet included in said second branch for operating said relay switch, an overload coil included in said running circuit, an armature operated by said overload coil for operating said circuit breaker, and means under the control oi? said relay magnet for setting said overload armature in ditlerent positions with respect to said overload coil for varying the sensitiveness of said overload circuit breaker.

16. In apparatus of the character described, a main motor provided with a field winding, a pilot motor provided with a field winding, a pilot motor operating circuit independent of said main motor and including said pilot motor field winding, a rheostat operated by said pilot motor, a second field winding for said pilot motor, a starting circuit for said main motor including said rheostat, said second pilot motor field winding and the armature of said main motor, a running circuit for the main motor, and means in circuit with the main motor field winding for controlling said main motor running circuit, said main motor starting circuit including a relay which controls the main motor running circuitand is under the control of said running circuit controlling means.

17. In apparatus of the character described, a main motor provided with a field winding and an armature, a circuit for energizing said field winding independently of said armature, a pilot motor having a field winding and an armature, a circuit including separable contacts for energizing said pilot. motor armature and field winding, means included in said main motor field winding energizing circuit .for operating said separable contacts, a rheostat operated by said pilot motor, a second field winding for said pilot motor, a starting circuit for the main motor armature, including said rheostat and second pilot motor field winding, and a running circuit for said main motor armature.

18. In apparatus of the character dcscribed, a main motor provided with a field winding and an armature, a circuit for energizing said field Winding independently of said armature, a pilot motor having a field winding and an armature, a circuit including separable contacts for energizing said pilot motor armature and field winding, means included in said main motor field winding energizing circuit for operating said separable contacts, a rheostat operated by said pilot motor, a second field winding for said pilot motor, a starting circuit for the main motor armature, including said rheostat and second pilot motor field winding, a. shunt which short-circuits said pilot motor and rheostat, and a running circuit for said main motor under the control of said shunt.

19. In a system of the character described, a main motor, a running circuit therefor including a relay switch and a circuit breaker other than said relay switch, a starting circuit for said main motor comprising a rheostat branch and a second branch excluding said rheostat, a relay magnet included in said second branch for operating said relay switch, an overload coil included in said running circuit, an armature operated by said overload coil for operating said circuit breaker, and means under the control of said relay magnet for setting said overload armature in dilierent positions with respect to said overload coil for varying the sensitiveness of said overload circuit breaker, a pilot motor for controlling said starting circuit, an operating circuit for said pilot motor, and means operated by said relay magnet for breaking said pilot motor operating circuit.

20. In apparatus of. the character described, a main motor, a starting circuit therefor, a pilot motor for controlling said starting circuit, an operating circuit for'said pilot motor including separable contacts, a running circuit for said main motor, means under the control of said pilot motor for changing from the starting circuit to the running circuit, and means operated by the first-mentioned means for operating said separable contacts in the pilot motor operating circuit, the first-mentioned means ineluding a relay energized by the starting circuit and the second-mentioned means in cluding a lever displaced by said relay and separating said contacts.

21. In apparatus of the character described, a motor, an energizing circuit for said motor, a relay for controlling said energizin circuit, an energizing circuit for said relay including a circuit-breaker, and means undelthe control of said relay for varying the degree of sensitiveness of said circuitbreaker, said circuit breaker having an overload coil in said motor energizing circuit, an armature subject to said coil, and means under the control, of said relay for changing the normal position of rest of said armature.

22. In a system of the character described, a main motor, a rheostat for starting the same, a pilot motor for operating said rheostat, a circuit-breaker comprising separable contacts in circuit with said pilot motor and an overload coil, a starting circuit for said main motor including a field winding for said pilot motor and said rheostat, a running circuit for said main motor, a relay for controlling said running circuit, and an energizing circuit for said relay including said separable contacts.

JOSEPH E. FELLER. 

